fix: mark some assets as not mounted by default

Author: craftablescience

legacy_schrodinger/addon.kv3

@@ -22,4 +22,5 @@
 	assets = 
 	{
 	}
-}
+	mounted_by_default = false
+}

p1_pgun/addon.kv3

@@ -24,4 +24,5 @@
 	assets = 
 	{
 	}
-}
+	mounted_by_default = false
+}

player_blood/addon.kv3

@@ -18,4 +18,5 @@
 	assets = 
 	{
 	}
-}
+	mounted_by_default = false
+}

unused_turret_vo/addon.kv3

@@ -21,4 +21,5 @@
 	assets = 
 	{
 	}
-}
+	mounted_by_default = false
+}